Null Pointer exception and intent error

Null Pointer exception and intent error

My App Always crash whenever I click on a button... the button gets text
from an edittext, and i believe that that is why i have a null pointer
exception. First question: how can i check if the editText is empty? I
already tried .equals(""), .equals(null), same with matches, and .lenght
== 0 Second, when i try to call the intent for my listActivity class i get
a handling error. (Activity not found. No activity to handle.) Ill give
you my onClickListener
ON CLICK LISTENER
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
searchInEnglish = rSearchEnglish.isChecked();
searchInDovahzul = rSearchDovahzul.isChecked();
searchBox = (EditText) findViewById(R.id.tvSearch);
if (searchBox.getText().toString().equals("")){
if (searchInEnglish) {
int counter = 0;
for (int i = 0; i < englishArray.length; i++) {
if
(englishArray[i].contains(searchBox.getText()))
{
counter++;
Intent search = new Intent(
"net.fernandezgodinho.pedro.dovahzuldictionary.SEARCHLIST");
startActivity(search);
}
}
setFinalSearch(searchResultsEnglish);
}
if (searchInDovahzul = true) {
int counter = 0;
for (int i = 0; i < dovahzulArray.length; i++) {
if
(dovahzulArray[i].contains(searchBox.getText()))
{
counter++;
Intent search = new Intent(
"net.fernandezgodinho.pedro.dovahzuldictionary.SEARCHLIST");
startActivity(search);
}
}
}
} else {
Toast.makeText(MainActivity.this, "Please use at least
two characters", Toast.LENGTH_LONG).show();
}
}
});